1. Field of the Invention
The present invention relates to certain methods or systems for forming and assembling subsystems for use in fluidic systems, and to the subsystems resulting from such formation and assembly.
2. Description of Background Information
Two main types of propulsion systems include chemical propulsion systems and electric propulsion systems. Some electric propulsion devices include the Xenon ion thruster (Kaufman Ion Bombardment), the Hall effect thruster, the arcjet, the pulsed plasma thruster, and the resistojet. Other electric propulsion devices include the magnetoplasma dynamic (MPD) thrusters, contact ion thrusters, and pulsed induction thrusters. Some chemical propulsion devices include cold gas devices which use cold gas propellants, such as nitrogen, argone, ammonia, or freon 14, and liquid propellant devices which use either a monopropellant or a bipropellant. Some common monopropellants include hydrazine (N2H4) and hydroperoxide (H2O2).
Chemical and electric propulsion systems incorporate subsystems (e.g., flow control, pressure transducers, etc.) each of which comprises fluidic, electrical, and mechanical structures. These subsystems typically comprise separately machined components assembled to form a given subsystem or module. Those components may comprise, e.g., one or more of low and high thrust engines, pressurant storage tanks, pressure regulators, isolation valves, filters, fill and vent valves, fill and drain valves, pressure transducers, temperature transducers, propulsion system electronics, and heaters. The components may also comprise electronic components such as driver circuits for engine valves, latching valves, solid state latches for thermal environment control heaters, signal conditioning circuitry, power converters, voltage regulators, and control logic.
There is a need for improved methods for forming assemblies of these different components in the form of integrated modules, and for such methods which facilitate the integrated assembly of modules, comprising various fluidic, electric, and mechanical components, at a low cost. The resulting modules also should be of a low weight, dependable in their operation, and take up a minimum amount of space. There is also a need for low flow-rate systems suitable for the very small flow rates required by electric propulsion systems. In addition, very small chemical and electric propulsion systems are required for many satellite and micro-satellite applications.
In view of the above, the present invention, through one or more of its various aspects and/or embodiments, is thus presented to bring about one or more objects and advantages such as those noted below.
An object of the present invention is to provide a method for forming and assembling etched sheet layers to create a fluidic module (i.e., a module comprising fluidic components). Another object of the present invention is to form such an integrated module comprising mechanical, fluidic, and electrical components, all fabricated in one unified assembly or module, comprising multiple layers attached to each other.
A further object of the present invention includes providing a method for forming integrated modules serving as subsystems and propulsion systems, where such modules are of a reduced size, weight, power consumption, and cost. Such modules preferably will be robust, and made of dependable materials. The modules may comprise high precision components, such as flow resistors and filters utilized in propulsion systems.
The present invention, therefore, is directed to a method or system for forming and assembling etched sheets to create a fluidic modular subsystem, and to the modular subsystems resulting from such a method or system. More specifically, the present invention, in one aspect, is directed to a process for forming a modular subsystem of a fluidic system by assembling a set of chemically etched sheets of material. The modular subsystem comprises mechanical, electrical, and fluidic components. Plural sheet members are provided. Respective ones of the sheet members are etched to form portions of mechanical, electrical, and fluidic components. The sheet members forming a given set are attached to each other to form a modular subsystem comprising the mechanical, electrical, and fluidic components. The fluidic system may comprise a propulsion system.
In accordance with another aspect of the present invention, a modular subsystem of a fluidic system is provided, which is assembled from a set of chemically etched sheets of material. The modular subsystem comprises a set of sheet members attached to each other. Each sheet member within the set is etched so that the mechanical, electrical and fluidic components will be formed when the sheet members are attached to each other. The fluidic system may comprise a propulsion system.